Process of extracting nut oil



Patented Oct. 7, 1930 UNITED 'QSTATES PATENT ounce THOMAS M. REOTOR, OF RUTHERFORD, JERSEY, ASSIGNOR TO FRANKLIN BAKER COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY PBOOESS OF EXTRACTING NUT OIL No Drawing.

My invention relates-to the extraction of oil from nut shells, and especially cashew shells, although it is notnecessarily limited to extraction from these particular shells.

The shell of the cashew nut contains a valuable oil, and the kernel is also valuable, and it is desirable to so process the nuts that the tough shell is conditioned for relatively easy removal while the shell oil is at the same time extracted, without injury to the kernel. Methods heretofore used or proposed involve heating, and have various disadvantages, 1ncluding burning and waste of some of the 01]. or damage to the kernels, as well as fire rlsk; and while various apparatus, expedients or precautions have been proposed to prevent or minimize burning or reduce the temperature or duration of' heating, these are all more or less unsatisfactory for various reasons known to persons skilled in this art.

The general object of the present invention is to provide an entirely novel method of extracting the shell oil, which practically or entirely eliminates the possibility of burning or other waste of the oil, fire risk, etc., with small or no injury to the kernels, and at the same time properlyconditions the shell for ready removal.

To this end the process consists, as briefly described, in submerging the whole nuts in a bath of molten metal or metallic alloy having a relatively low melting po'int, su ch, for example, as an alloy of lead and t1n 1n proportions which maybe varied considerably to control the melting point and temperature at which the bath must be kept to allow for the cooling effect of the introduction of fresh nuts and avoid solidification of the bath. One suitable alloyis a composition of the stated metals-in such proportions that the melting point is approximately 400 E, and

the bath may be maintained ata moderatelyhigher temperature, suficient to prevent solidification upon introduction of the nuts.

The time of submersion may vary in accordance with the temperature of the bath, condition of the nuts, and other factors. W1th a loath of stated composition, and at about the stated temperature the nuts may be submerged for from approximately to 60 sec- Application filed November 8, 1 928. Serial No. 318,107.

onds. In this time a large proportion of the shell oil is driven off into the bath and rises to the surface thereof, overlying the metal. I have demonstrated by careful weight tests that the oil extracted in the bath amounts to approximately 12% of the weight of the raw nuts, which compares favorably with the percentage of extraction obtained by processes previously known or proposed including the, open pan process commonly used in India.

Simultaneously with extraction of oil the shells are rendered brittle and swelled and otherwise conditioned for shelling, so that the shells may be removed from the kennels, after the nuts are removed from the bath, with satisfactory speed and economy. The whole nuts, or the shells, after removal from the kernels, may be treated with a suitable solvent, such as alcohol or other organic solvent, to remove oil adhering to or remaining in the shells, after which the oil is recovered from the solvent in any known or suitable manner, as for example by di'stillation.

The extracted oil may-be drawnofli continuously or intermittently, cooled and stored. Any suitable apparatus may beemployed ,for carrying out the process, which may be conducted byhand manipulation or bypartly or entlrely automatic mechanism. For example, the molten bath may be in atrough of sufficient length to contain'a suit-able number,

say three or more, baskets in which the nuts are placed, A track may be-provided at the bottom of the trough, over which the baskets aremoved to submerge the nuts in the molten bath and advance thenithroughit. At a suitable interval, depending on the time of treatment and the number of baskets in the trough, a'freshly charged basket is pushed in at one end and .a-basket of treated nuts is ejected, at the other end of thetrough. Thus, if the trough is arranged to hold threebaskets, a fresh basket willvbe inserted at intervals of from 12 to 15 seconds, under conditions of the process specifically referred to herein above as an example, so that each basket will of each basket of fresh nuts.

Without the use of baskets.

scope of the claims appended.

I claim:

1. A process of extracting oil from nut shells, including as a characteristic step the placing of the shells in a bath of molten metal having a comparatively low melting point.

2. A process of extracting oil from nut shells, including as a characteristic step the placing of the SllQllS HI a bath of molten metal having a comparatively low melting point, the bath being maintained at a temperature moderately above the melting point, sufficient to prevent solidification by the cooling efiect of shells introduced.

3. A process of extracting oil from nut shells, including as a characteristic step the placing of the shells in a bath of molten metal having a melting point not higher than approximately 400 F.

4. A process of extracting oil from nut shells, including as a characteristic step the placing of the shells in a bath of molten mei tallic alloy having a melting point not higher than approximately 400 F.

5. A process of extracting oil from nut shells, including as a characteristic step the placing of the shells in a bath of molten metal maintained at a temperature suflicient to expel from the shells a substantial percentage of their contained oil which rises to the surface of the metal bath.

6. A process of extracting oil from nut 6B shells, including as a characteristic step the remain in the bath from approximately 50 to 00 seconds, one basket of treated nuts being e ected simultaneously with the insertion 5 When desired a continuously or intermittently moving conveyor may be arranged to move the baskets or trays of nuts through the bath at a proper rate.or the nuts may be submerged and advanced through the bath 10 by cross pieces on a continuous conveyor,

Metals or alloys having low melting point, suitable for this process, such for example as lead or its alloys, oxidize rapidly in the 5 presence of air. Such oxidization is, however, largely or almost entirely prevented by the fact that the extracted oil lies above the metal and excludes air therefrom, practically or entirely preventing oxidization.

20 WVhen a suitable metal or alloy is employed, capable of extracting the oil at reasonable temperature, for example as above described, the oil is not decomposed or evaporated or otherwise Wasted or deteriorated to any con- 5 siderable or prejudicial extent.

The process is not limited to stated alloy. Any metal or metallic alloy having a sufiiciently low melting point may be employed, or other variations may be made 3 in the process, as Will be understood by skilled persons from the preceding explanation and specific example, and as contemplated in the the use of the placing of the shells in a bath of a molten metallic alloy having a comparatively low melting point.

7. A process of extracting oil from nut shells, including as a characteristic step the placing of the shells in a bath of molten metallic alloy maintained at a temperature sutficient to expel from the shells a substantial percent-age of their contained oil which rises to the surface of the metal bath.

8. A process of extracting oil from nut shells, including as a characteristic step the placing of the shells in a bath of molten metallic alloy including lead and having a comparatively low melting point.

9. A process of extracting oil from nut shells, including as a characteristic step the placing the shells in a bath of a molten metallic alloy containing lead and tin and having a comparatively low melting point.

10. A process of extracting oil from nut shells, including as a characteristic step the placing of the shells in a bath of molten metallic alloy of lead and tin and having a comparatively low melting point.

11. A process of extracting oil from nut shells, including as a characteristic step the placing of the shells in a bath of molten metallic alloy including lead and having a melting point not higher than approximately 400 F.

12. A process of extracting oil from nut shells, including as a characteristic step the placing of the shells in a bath of molten metallic alloy containing lead and tin and having a melting point not higher than approximately 400 F.

13. A process of extracting oil from nut shells, including as a characteristic step the placing of the shells in a bath of molten metal having a comparatively low melting point, the shells being submerged in the bath for a time sufiicient to produce extraction of a desired percentage of their contained oil and condition the shells for easy removal, and insufiicient to injure the kernels.

14. A process of extracting oil from nut shells, including as a characteristic step the placingof the shells in a bath of a molten metallic alloy having a comparatively low melting point, the shells being submerged in the bath for a time sufficient to produce ex- 1 A metal having a comparatively low melting point.

17. A process of extracting oil from cashew nut shells, including as a characteristic step the placing of the whole nuts in a bath of molten metal having a comparatively low melting point.

18. A process of extracting oil from cashew nut shells including as a characteristic step.

the placing of whole nuts in a bath of a molten metallic alloy having a comparatively low melting point.

In testimony whereof I aflix my signature.

THOMAS M. HECTOR. 

